Abstract
Provided is an injection-molded resin button, which does not crack or is unlikely to crack at attaching the button to a fabric. This invention relates to a button including a button body having a through-hole at the center thereof. The button body of the button includes a left half part and a right half part, which are segmented left and right by a virtual straight line passing through a gate position, on the button body, corresponding to a gate of a mold for molding the button and the center of the button body. The button body includes one or more concave portions or one or more convex portions on an outer surface of the button body. The button is characterized in that the concave portions or the convex portions are provided asymmetrically in the left and right half parts. The button body includes a nonlinear weld line at least on the outer surface.
Claims
1. An injection-molded resin button (10, 10a, 10b, 10c) comprising a button body (11) having a through-hole (13) at the center thereof: wherein the button body (11) comprises a left half part (11L) and a right half part (11R), the left and right half parts (11L, 11R) being segmented left and right by a virtual straight line (L) passing through a gate position (17), on the button body (11), corresponding to a gate of a mold for molding the button (10, 10a, 10b, 10c) and the center (0) of the button body (11), wherein the button body (11) includes one or more concave portions (21, 22, 23, 24, 25, 26, 27, 28, 29) or one or more convex portions (31, 32) on an outer surface (11a) of the button body (11), the concave portions (21, 22, 23, 24, 25, 26, 27, 28, 29) or the convex portions (31, 32) being provided asymmetrically in the left and right half parts (11L, 11R), the outer surface is a surface of the button body oriented to come into contact with a fabric to which the button is attached.
2. The button according to claim 1, wherein the button body (11) includes a weld line (16, 16a, 16b, 16c), and wherein the weld line (16, 16a, 16b, 16c) appears as a nonlinear line at least on the outer surface (11a) of the button body (11).
3. The button according to claim 2, wherein the weld line (16, 16a, 16b, 16c) appears as a nonlinear line on an inner surface (11b) of the button body (11).
4. The button according to claim 2, wherein the weld line (16, 16a, 16b, 16c) appears as a nonlinear line on a peripheral surface defining the through-hole (13) of the button body (11).
5. The button according to claim 2, wherein the weld line (16, 16a, 16c) appearing on the outer surface (11a) of the button body (11) is at least partially zigzag.
6. The button according to claim 1, wherein the left half part (11L) and the right half part (11R) are different in volume.
7. The button according to claim 1, wherein the left half part (11L) includes one or more left arc concave portions (21, 22, 23, 24) or left arc convex portions extending or arranged in an arc shape in the circumferential direction around the center (0), wherein the right half part (11R) includes one or more right arc concave portions (25, 26) or right arc convex portions (31, 32) extending or arranged in an arc shape in the circumferential direction, and wherein the left arc concave portions (21, 22, 23, 24) or left arc convex portions and the right arc concave portions (25, 26) or right arc convex portions (31, 32) are displaced from each other in the radial direction.
8. The button according to claim 1, wherein the left half part (11L) includes one or more left arc concave portions (28) or left arc convex portions extending or arranged in an arc shape in the circumferential direction around the center (0), wherein the right half part (11R) includes one or more right arc concave portions (29) or right arc convex portions extending or arranged in an arc shape in the circumferential direction, and wherein the left arc concave portions (28) or left arc convex portions and the right arc concave portions (29) or right arc convex portions are at the same location in the radial direction and different in length in the circumferential direction.
9. The button according to claim 1, wherein the left half part (11L) or the right half part (11R) includes one or more first arc concave portions (21, 23) or first arc convex portions (31) extending or arranged in an arc shape in the circumferential direction around the center (O), and one or more second arc concave portions (22, 24) or second arc convex portions (32) extending or arranged in an arc shape in the circumferential direction, the second arc concave portions (22, 24) or second arc convex portions being provided with an interval in the radial direction relative to the first arc concave portions (21, 23) or first arc convex portions (31).
10. The button according to claim 1, wherein only one of the left half part (11L) and the right half part (11R) includes one or more concave portions (27) or convex portions on the outer surface (11a).
11. The button according to claim 1, wherein the button (10, 10a, 10b, 10c) is a female snap button (10, 10a, 10b, 10c), wherein the button body (11) is a bottom portion (11) of the female snap button (10, 10a, 10b, 10c), and wherein the female snap button (10, 10a, 10b, 10c) includes a peripheral side portion (12) protruding from a radially outer end of the bottom portion (11).
Description
BRIEF DESCRIPTION OF DRAWINGS
(1) FIG. 1 is a perspective view of a female snap according to a first embodiment of the present invention.
(2) FIG. 2 is a bottom view of the female snap of FIG. 1;
(3) FIG. 3 is a cross-sectional view taken along the line A-A in FIG.
(4) FIG. 4 is a cross-sectional view showing a state in which a female snap is attached to a fabric by a button fastener.
(5) FIG. 5 is a bottom view of a female snap according to a second embodiment of the present invention.
(6) FIG. 6 is a bottom view of a female snap according to a third embodiment of the present invention.
(7) FIG. 7 is a cross-sectional view taken along the line B-B in FIG. 6.
(8) FIG. 8 is a bottom view of a female snap according to a fourth embodiment of the present invention.
(9) FIG. 9 is a cross-sectional view taken along the line C-C in FIG. 8.
(10) FIG. 10 is a perspective view of a conventional female snap.
(11) FIG. 11 is a bottom view of the female snap in FIG. 10;
(12) FIG. 12 is a cross-sectional view taken along the line D-D of FIG. 11.
DESCRIPTION OF EMBODIMENT
(13) Hereinafter, some embodiments of the present invention will be described with reference to the drawings. However, the invention is not limited to the embodiments, and those skilled in the art can suitably modify or alter them within the scope of the claims or the range of equivalents. FIGS. 1 and 2 are a perspective view and a bottom view of a female snap 10 as a button according to an embodiment of the present invention. FIG. 3 is a cross-sectional view taken along the line A-A in FIG. 2. Hereinafter, an upper or upward side and a lower or downward side are based on FIG. 3, and a vertical (up-and-down) direction is the thickness direction of the female snap button of FIG. 3. The female snap 10 is an injection-molded product made of synthetic resin, and includes a substantially disc-shaped bottom portion 11 as a button body and a peripheral side portion 12 that protrudes upward from a radially outer end of the bottom portion 11. In the center of the bottom portion 11, a through-hole 13 is provided for allowing the pin 122 of the button fastener 120 to pass when the female snap 10 is attached to a fabric 1 (see FIG. 4). A space 14 above the bottom portion 11 and radially inward of the peripheral side portion 12 of the female snap 10 is a receiving portion 14 that detachably receives an engagement projection of a male snap as not shown. At an upper end on the radially inner surface of the peripheral side portion 12, a bulge 15 bulging radially inward is provided. The bulge 15 is temporarily bent radially outward when the engagement projection of the male snap is received in and removed from the receiving portion 14. The reference numeral 18 in FIGS. 1 to 3 represents an annular edge 18, which slightly protrudes radially outward and is provided at the boundary with the bottom portion 11 on the radially outer side surface of the peripheral side portion 12. The lower surface (the outer surface in the claims) 11a of the bottom portion 11 gradually lowers radially inward from the annular edge 18 and then becomes horizontal. Thus, it can be said that the lower surface 11a of the bottom portion 11 is slightly convex downward.
(14) On the lower surface 11a, the upper surface 11b and the peripheral surface defining the through-hole 13 of the bottom portion 11 of the female snap 10, a nonlinear weld line 16 (see FIGS. 2 and 3) emerges. Further, on the peripheral side portion 12, a trace of the location corresponding to a gate (injection port) of a mold used for molding the female snap 10 slightly remains, and this is a gate position 17. The gate position 17 is located at the top in FIG. 2. The bottom portion 11 of the female snap 10 is virtually segmented into a left half part 11L and a right half part 11R by a virtual straight line L connecting the gate position 17 and the center O of the female snap 10. In the present embodiment, the weld line 16 on the lower surface 11a of the bottom portion 11 extends radially outward from the through-hole 13 to the radially outer end of the bottom portion 11 as follows. Firstly, in the radially inward end on the through-hole 13 side, the weld line 16 begins in the right half part 11R and goes into the left half part 11L across the virtual straight line L and then goes back from the left half part 11L to the right half part 11R across the virtual straight line L. After the weld line 16 extends in the above-mentioned zigzag shape, the weld line 16 further extends radially outward almost along the virtual straight line L. After this, the weld line 16 goes into the left half part 11L and then terminates at the radially outer end. The weld line 16 is also nonlinear in the vertical direction of the bottom portion 11, and the vertically zigzag weld line 16 appearing on the peripheral surface defining the through-hole 13 is shown in FIG. 3. Although not shown, the weld line 16 appearing on the upper surface 11b of the bottom portion 11 is different in shape from the weld line 16 appearing on the lower surface 11a.
(15) In the left half part 11L of the bottom portion 11, a first left arc concave portion 21 and a second left arc concave portion 22 are formed. The first and second left arc concave portions 21, 22 extend in an arc shape in the circumferential direction around the center O, and the second left arc concave portion 22 are located radially outward from the first left arc concave portion 21 with an interval 41. In this embodiment, the width along the radial direction of each of the first and second left arc concave portions 21, 22 is the same, and the degree of depression from the lower surface 11a of each of the first and second left arc concave portions 21, 22 is also almost the same. In the right half part 11R of the bottom portion 11, a first right arc convex portion 31 and a second right arc convex portion 32 are formed. The first and second right arc convex portions 31, 32 extend in an arc shape in the circumferential direction, and the second right arc convex portion 32 are located radially outward from the first right arc convex portion 31 with an interval 42. The first and second left arc concave portions 21, 22 and the first and second right arc convex portions 31, 32 extend about 170 degrees in the circumferential direction. In this embodiment, the width along the radial direction of the second right arc convex portion 32 is about twice the width along the radial direction of the first right arc convex portion 31. Further, the degree of protrusion from the lower surface 11a of each of the first and second right arc convex portions 31, 32 is almost the same. Further, the first right arc convex portion 31 is located, in the radial direction, between the first and second left arc concave portions 21, 22. In other words, the first right circular arc convex portion 31 is displaced in the radial direction from the first and second left arc concave portions 21, 22. The second right arc convex portion 32 is formed radially outside the second left arc concave portion 21. As described above, in the left and right half parts 11 L, 11R of the bottom portion 11 of the female snap 10, the first and second left arc concave portions 21, 22 as concave portions and the first and second right arc convex portions 31, 32 as convex portions are provided bilaterally asymmetrically. In this embodiment, the volume of the left half part 11L including the first and second left arc concave portions 21, 22 is smaller than the volume of the right half part 11R including the first and second right arc convex portions 31, 32.
(16) As in the above example, the weld line 16, which is generated by left and right resin flows joined at molding the female snap 10, can be extended in a zigzag shape such as by providing the left half part 11L with the concave portions (21, 22) and providing the right half part 11R with the convex portions (31, 32); further displacing the concave and convex portions (21, 22; 31, 32) in the radial direction; changing the radial width of each of the convex portions (31, 32). Furthermore, the first and second left arc concave portions 21, 22 are arranged in the radial direction of the bottom portion 11 with the interval 41 between them, and similarly the first and second right arc convex portions 31, 32 are also radially arranged with the interval 42 between them. This way, providing the intervals 41, 42 also helps to extend the weld line 16 so as to increase leftward and rightward swing in a zigzag shape. In this embodiment, the radial width of the interval 41 of the left half part 11L is larger than radial width of the first right arc convex portion 31, which is arranged at the same radial position as with the interval 41. This is also considered to promote a zigzag extension of the weld line 16. The interval 42 of the right half part 11R has almost the same radial width as that of the second left arc concave portion 22, which is arranged at the same radial position as with the interval 42. In this way, it is preferable that the width in the radial direction each of the intervals 41, 42 is larger than or equal to the radial width of convex or concave portion arranged, in other half part, at the radial position corresponding to the intervals 41, 42.
(17) The first and second left arc concave portions 21, 22 as described above are molded by convex portions provided on a cavity surface of a mold (not shown) for molding the female snap 10, and the first and second right arc convex portions 31, 32 are molded by concave portions on the cavity surface. In this way, since the mold is provided with convex and concave portions bilaterally asymmetrically, the nonlinear weld line 16 shown in FIG. 2, etc. is generated. That is, when the female snap 10 is molded, a melted resin material injected into the cavity through the gate of the mold is once divided into left and right flows by a center core corresponding to the through-hole (the material is divided into a left half part and a right half part of the cavity by a virtual straight line passing through the gate and the center of the cavity (core)). The left and right divided flows meet and join again behind the core. At this time, resistances to the left and right divided flows or velocities thereof are different in the left and right half spaces of the cavity, and therefore the spot where the resign flows joined will not become a linear line, resulting in the weld line 16 that is at least partially zigzag. Thereby, when the female snap 10 is attached to the fabric 1, the bottom portion 11 does not crack or is unlikely to crack along the weld line 16.
(18) FIG. 4 is a cross-sectional view showing a state in which the female snap 10 is attached to the fabric 1 with the button fastener 120. The button fastener 120 comprises a substantially disk-shaped base 121 and a pin 122 protruding from a center area of the base 121. When the female snap 10 is attached to the fabric 1 using the button attachment machine, the pin 122 of the button fastener 120 penetrates the fabric 1 upward and passes through the through-hole 13 of the female snap 10. After this, the pin 122 is swaged as being crushed by a punch as not shown. Thereby, the female snap 10 is fixed to the fabric 1. Since the pin 122 of the button fastener 120 comes into the through-hole 13 of the female snap 10 along with a portion of the fabric 1 being pulled by the pin 122, the bottom portion 11 receives a force to radially expand the through-hole 13. Such a force is considered to be the cause of cracking along the weld line 16 having a relatively low strength. In this embodiment, with the bilaterally-asymmetric convex and concave portions as stated above, it is possible to intentionally extend the weld line 16 in a zigzag shape, the weld line 16 being a spot of joining left and right resin flows. Thereby, strength of the resin-joining spot increases, decreasing or eliminating the above-mentioned cracking. As shown in FIG. 4, the female snap 10 is attached to the fabric 1 so that the lower surface 11a of the bottom portion 11 faces the fabric 1. Therefore, concave portions (or convex portions) provided on the lower surface 11a of the bottom portion 11 are not seen by a user after the female snap 10 is attached to the fabric 1. On the other hand, the upper surface 11b of the bottom portion 11 is visible to a user even after being attached to the fabric 1. Therefore, it is possible to form concave portions (or convex portions) on the lower surface 11a of the bottom portion 11 without considering aesthetic appearances when the arbitrary, nonlinear weld line 16 is formed.
(19) FIG. 5 is a bottom view showing a female snap 10a as a button according to a second embodiment of the present invention. Since the female snap 10a is common to the female snap 10 except for concave portions 23, 24, 25, 26 as described below, same reference numerals as with the female snap 10 are used except for the concave portions 23, 24, 25, 26 and descriptions thereof are omitted. The female snap 10a is provided with concave portions on the lower surface 11a of the bottom portion 11 as follows. The left half part 11L of the bottom portion 11 includes four first left concave portions (one left arc concave portion) 23 arranged in an arc shape in the circumferential direction around the center O, and four second left concave portions (one left arc concave portion) 24 arranged radially outward from the first left concave portions 23 with an interval and in a circumferentially arc shape. Each of the first left concave portions 23 has a square or trapezoidal shape with rounded corners. Each of the second left concave portions 24 has a square shape with rounded corners, and is approximately twice as large as each of the first left concave portions 23. Further, the right half part 11R of the bottom portion 11 includes four first right concave portions (one right arc concave portion) 25 arranged in an arc shape in the circumferential direction, and four second right concave portions (one right arc concave portion) 26 arranged radially outward from the first right concave portions 25 with an interval and in a circumferentially arc shape. Each of the first right concave portions 25 has a square shape with rounded corners. Each of the second right concave portion 26 has a square or trapezoidal shape with rounded corners, and is approximately twice as large as each of the first right concave portions 25. Further, the first right concave portions 25 are provided, in the radial direction, between the first and second left concave portions 23, 24, and the second right concave portions 26 are provided radially outward from the second left concave portions 24. Furthermore, each of the first right concave portions 25 is larger than each of the first left concave portions 23, and each of the second right concave portions 26 is larger than each of the second left concave portions 24. In the female snap 10a, the volume of the left half part 11L is larger than that of the right half part 11R. The female snap 10a is molded by a mold, which includes a cavity having convex portions corresponding to the concave portions 23, 24, 25, 26. On the lower surface 11a of the bottom portion 11 of the female snap 10a, a zigzag weld line 16a shown in FIG. 5 is generated. The radially inner end of the weld line 16a is located on the virtual straight line L. The weld line 16a goes radially outward into the left half part 11L from the radially inner end; then returns rightward going into the right half part 11R across the virtual straight line L; then returns leftward going into the left half part 11L across the virtual straight line L again; then returns rightward again going into the right half part 11R across the virtual straight line L; and extends to and terminates at the radially outer end. In the female snap 10a, the bottom portion 11 hardly cracks along the weld line 16a when the female snap 10a is attached to the fabric.
(20) Further, in the female snap 10a of the second embodiment, there are three flat portions between two of the four first left concave portions 23 formed in the left half part 11L of the bottom portion 11a. These flat portions are not concave or convex and define the lower surface 11a of the bottom portion 11. It can be said that each of the flat portions is a spot in which more resin material gathered than in each of the first left concave portions 23. That is, in a circumferentially arc shaped region where the four first left concave portions 23 are provided, the portions (flat portions) having more resin are also arranged in an arc shape along the circumferential direction. Similarly, as to the second left concave portions 24 and the first and second right concave portions 25, 26, the portions (flat portions) each having more resin material than each corresponding concave portion are formed and arranged in a circumferentially arc shape between two of the respective second left, first and second right concave portions 24, 25, 26. In this way, in the bottom portion 11, portions (flat portions) having more resin material than concave portions are arranged in an arc shape in the circumferential direction. Thereby, it is possible to make the weld line 16a nonlinear, strengthening the female snap 10.
(21) FIG. 6 is a bottom view of the female snap 10b according to the third embodiment of the present invention. FIG. 7 is a cross-sectional view taken along the line B-B in FIG. 6. Regarding part of the female snap 10b that is common to the female snap 10, same reference numerals as with the female snap 10 are used and descriptions thereof are omitted. The female snap 10b includes one concave portion 27 that extends in an arc shape in the circumferential direction in only the right half part 11R on the lower surface 11a of the bottom portion 11. The concave portion 27 extends approximately 170 degrees in the circumferential direction. That is, there are no concave and convex portions in the left half part 11L. In this way, by providing the concave portion 27 only in the right half part 11R, the following weld line 16b is formed on the lower surface 11a of the bottom portion 11 of the female snap 10b. That is, referring to FIG. 6, the weld line 16b extends radially outward from a left-right intermediate point on the through-hole 13 side almost on the virtual straight line L and gradually goes into the right half part 11R. Then, the weld line 16b extends radially outward further, gradually turning leftward toward the virtual straight line L from an almost intermediate point in the radial direction, and terminates at the radially outer end of the bottom portion 11 almost on the virtual straight line L. That is, the weld line 16b is generated so as to enter the right half part 11R where the concave portion 27 lies. The weld line 16b is a curved line not including a zigzag portion and is nonlinear. This weld line 16b can also prevent the female snap 10b from cracking when it is attached to the fabric 1.
(22) FIG. 8 is a bottom view of the female snap 10c according to the fourth embodiment of the present invention, and FIG. 9 is a cross-sectional view taken along the line C-C in FIG. 8. Regarding part of the female snap 10c that is common to the female snap 10, same reference numerals as with the female snap 10 are used and descriptions thereof are omitted. The female snap 10c includes a left arc concave portion 28 extending in the circumferential direction on the lower surface 11a of the left half part 11L of the bottom portion 11 and a right arc concave portion 29 circumferentially extending on the lower surface 11a of the right half part 11R. The left arc concave portion 28 circumferentially extends approximately 40 degrees in the upper half of the left half part 11L based on FIG. 8. The right arc concave portion 29 circumferentially extends approximately 170 degrees in the right half part 11R. The circumferential length of the left arc concave portion 28 is approximately half of that of the right arc concave portion 29. The left arc concave portion 28 and the right arc concave portion 29 are at the same position in the radial direction. Further, the radial width of the left arc concave portion 28 is slightly larger than that of the right arc concave portion 29. In this way, by providing the left and right arc concave portions 28, 29 located at the same radial position and having different circumferential lengths, the following zigzag weld line 16c is generated on the lower surface 11a of the bottom portion 11 of the female snap 10c. That is, referring to FIG. 8, the weld line 16c extends from a left-right intermediate point on the through-hole 13 side almost on the virtual straight line L to go into the left half part 11L; then turns rightward toward the virtual straight line L; goes into the right half part 11R across the virtual straight line L; and then turns leftward to terminate at the radially outer end of the bottom portion 11 almost on the virtual straight line L. The weld line 16c enters the right half part 11R at a radial position where the left and right arc concave portions 28, 29 lies. This weld line 16c can also eliminate or reduce cracking of the female snap 10c at attaching the female snap 10c to the fabric 1.
DESCRIPTION OF REFERENCE NUMERALS
(23) 10, 10a, 10b, 10c female snap button (button) 11 bottom portion (button body) 11a lower surface of bottom portion (outer surface) 11b upper surface of bottom portion (inner surface) 12 peripheral side portion 13 through-hole 14 receiving portion 15 bulge 16, 16a, 16b, 16c weld line 17 gate position 21, 23 first left arc concave portion (concave portion) 22, 24 second left arc concave portion (concave portion) 25 first right arc concave portion (concave portion) 26 second right arc concave portion (concave portion) 27 concave portion 28 left arc concave portion (concave portion) 29 right arc concave portion (concave portion) 31 first right arc convex portion (convex portion) 32 second right arc convex portion (convex portion) L virtual straight line O center
